Streamer adapted for towing by aircraft



March 22, 1938. c. D. YOUNG' 2,112,204

STREAMER ADAPTED FOR TOWING BY AIRCRAFT Filed May 11, 1933 v v N I INVENTOR: dharw/sl). 16mg,

Patented Mar. 22, 1938 UNITED STATES PATENT STREAMER ADAPTED FOR TOWING BY AIRCRAFT Charles D. Young, Haverford, Pa., assignor to Kellett Autogiro Corporation,

Philadelphia,

6 Claims.

This invention relates to streamers adapted 'for towing by aircraft, and more particularly to streamers bearing words or symbols displayed thereon in such manner as to constitute a sign clearly legible from the ground and therefore useful for the purpose of advertising. The streamer of this invention may also be used to advantage in aerial signalling, as an aerial target for anti-aircraft fire, and for other purposes, wherever it is desired tomake an announcement to the ground quickly over a large area.

Generally stated the object of my invention is to provide a streamer of simple and inexpensive construction so designed that when towed behind an aeroplane or other aircraft it will assume a position in a substantially vertical plane with its longitudinal axis substantially paralleling level ground. More specifically the streamer .is characterized by a particular form of bridle at its leading edge and a flexible connection between the tow line and bridle, whereby under different conditions of flying speed and wind the streamer has capacity for self-adjustment iand' tends to maintain the desired position of flight.

Other objects and advantages characterizing my present invention will become more fully apparent from the description of certain examples or embodiments thereof which are hereinafterset forth with reference to the accompanying drawing. Of the drawing:

Fig. I represents a side elevation of a streamer of my invention with the tow line substantially taut.

Fig. 11 represents a similar view of the same, with slack in the tow line showing how the streamer adapts itself to changed. conditions; and,

Fig. III represents a side elevation of a portion of a. modified streamer in which the bridle is differently constructed.

With reference to the streamer illustrated in Figs. I and II, it will be observed that the same comprises a rectangular skeleton framework ineluding rigid vertical members I disposed in spaced parallel relation and longitudinal nonrigid members 2, 3 and 4, disposed at right angles to the vertical members I and parallel to each other. Preferably the vertical members I may take the form of bamboo poles, whereas the upper and lower longitudinal members 2, 3 are. desirably made of stout cord, and the intermediate longitudinal members 4 of finer cord; The letters or symbols 5 to be displayed on the framework of the streamer are secured by any suitable means to the intermediate longitudinal members 4, or they may extend from the upper longitudinal 2 to the lower longitudinal 3, the present invention not being concerned with the mode of attachment of the display sign to the framework.

At the forward or leading end of the streamer I employ a loop bridle 6 joining the upper and lower ends of the foremost vertical member I and forming therewith a triangular connection between the tow line i and the framework of the streamer. The tow line i terminates in an eye or thimble 8 surrounding the bridle 6 and slidable thereon. In order to give adequate strength to the foremost vertical member i without unduly increasing its weight, a strut 9 is positioned behind the member bracing it at its medial portion. The strut 9 is held in place by a stay wire l0 including a turnbuckle H by means of which the wire may be tautened to the desired degree.

While the streamer is illustrated in the drawing with a longitudinal axis assuming a horizontal position, it is to be understood that under actual flying conditions the longitudinal axis may be inclined to an angle of twenty degrees or thereabouts with the horizontal, and the words horizontal and vertical are therefore used herein in a general sense. Moreover, the streamer may be of considerably greater length in proportion to height than represented in the particular illustrated embodiment of the invention. Throughout the framework of the streamer I preferably employ diagonal members l2, one for each panel of the framework, the diagonals joining the upper end of each vertical member I with the lower end of the next vertical member to the rear thereof.

At the rear end of the streamer there is provided a trailing loop M in the form of a line joining the upper and lower ends of the rearmost vertical member I. The trailing loop I 4 constitutes a counterpart of the bridle 6 at the forward end of the streamer. To the trailing loop hi there is slidably connected a drag element I5 which may take the form of the wellknown wind sock, and which offers sufiicient resistance to maintain the stability of the streamer during flight. The drag element l5 preferably is attached to the trailing loop [4 by means of an eye or thimble it, or alternatively fixed wind socks are attached to the ends of the rearmost vertical member 5.

By the construction described above, the framework of the streamer is in effect pivoted for revolution about a longitudinal towing axis :c-a: which varies in its position according to the speed of the towing vehicle, wind conditions and other factors. In order to maintain the streamer in substantially vertical plane and Without causing it to sag intermediate its forward and rear ends, the framework is weighted at.

the two lower corners, the weights being attached to the foremost and rearmost vertical member as indicated at l1, l8, thus placing the center of gravity of the framework near its lower edge and well below the lowest position of the towing axis.

In Fig. III there is represented a modified form of streamer of my invention in which the loop bridle 6a includes stays 2i,- extending diagonally upward and downward from the center of the leading vertical member l and joining the loop bridle So at points designated at 2| and 22. With this construction the stays 28 reinforce the leading vertical member I against bending at its medial portion and thus perform a function equivalent to that of the strut 9 described with reference to the structure of Figs. I and II. The tow line i is slidably connected to the loop bridle (id, but its movement is confined within that portion of the bridle in advance of the points 2!, 22.

It is to be especially noted that in both forms of my invention the tow line i is'not fastened to any particular point of the bridle 6, but is free to move therealong. Heretofore it has been proposed to employ a fixed connection between the tow line and bridle and to utilize a number of auxiliary bridle lines leading from the inner section of the tow line and bridle to the medial portion of the foremost vertical member of the streamer. An example of such practice is illustrated in the patent to M. S. DuPont No. 1,901,- 855, issued March 14, 1933. By the provision of a loop bridle and flexible connection between the tow line and the same, the framework of the streamer has capacity for self-adjustment with respect to the tow line and hence tends to assume a position in which its longitudinal axis is substantially level irrespective of the degree of tautness of the tow line 1. This flexibility or capacity for adjustment is likewise characteristic of the drag element 15. In effect the streamer is supported flexibly between two movable points, and incident to changes in the speed of the towing vehicle or other conditions will tend to maintain the desired position. Moreover, the flexibility or capacity for self-adjustment is obtained in such manner as not to place undue strain upon the leading vertical member of the streamer, this member being adequately reinforced against bending at its medial portion.

In Fig. I the streamer is represented with the tow line I relatively taut. When the speed of the towing vehicle is decreased momentarily or when for other reason the tow line 1 becomes slackened, as represented with some exagggeration in Fig. II, the towing axis will assume a position more near the center line of the streamer. Under this condition the weights l1, ill will maintain the streamer in a substantially vertical plane and the towing bridle 6 will assume a differently shaped triangle. With a fixed connection between the tow line and bridle there is necessarily a tendency for the leading vertical member to assume a position substantially at right angles to the tow line. With the streamer constructed in the manner of my invention, the leading vertical member will tend to retain its vertical position with relation to the ground, irrespective of whether the tow line is relatively taut or relatively slack.

While I have described certain specific examples of the practice of my invention, it will be apparent, especially to those skilled in the art, that various changes may be made in the particular form of the streamer, its framework, bridle lines and reinforcing elements, all without departing from the spirit of the invention as defined in the annexed claims.

Having thus described my invention, I claim:

1. A streamer adapted for towing by aircraft comprising a. substantially rectangular skeleton framework including vertical and longitudinal members, the vertical members being rigid and the framework having a center of gravity nearer its lower edge, a loop bridle joining the upper and lower ends of the foremost vertical member, a tow line slidably connected to said loop bridle, and a drag element connected to the rear end of said framework.

2. A streamer adapted for towing by aircraft comprising a substantially rectangular skeleton framework including vertical and longitudinal members, the vertical members being rigid and the framework having a center of gravity nearer its lower edge, a loop bridle joining the upper and lower ends of the foremost vertical member, said foremost vertical member being reinforced against bending at its medial portion, a tow line slidably connected to said loop bridle, and a drag element connected to the rear end-of said framework.

3. A streamer adapted for towing by aircraft comprising a substantially rectangular skeleton framework including vertical and longitudinal members, the vertical members being rigid and the framework having a center of gravity near its lower edge, a loop bridle joining the upper and lower ends of the foremost vertical member, a strut reinforcing said foremost vertical member against bending at its medial portion, a tow line terminating in a thimble slidably mounted on said loop bridle, and a drag element connected to the rear end of said framework.

4. A streamer adapted for towing by aircraft comprising a substantially rectangular skeleton framework including vertical and longitudinal members, the vertical members being rigid and the framework having a center of gravity near its lower edge, a loop bridle joining the upper and lower ends of the foremost vertical member, stays extending diagonally upward-and downward from the center of said foremost vertical member, stays extending diagonally upward and downward from the center of said foremost vertical member and joining said loop bridle thereby reinforcing the same against bending, a tow line slidably connected. to the bight of the bridle between said stays, and a drag element connected to the rear end of said framework.

5. A streamer adapted for towing by aircraft comprising a substantially rectangular skeleton framework including vertical and longitudinal members, the vertical members being rigid and the framework having a center of gravity near its lower edge, a loop bridle joining the upper and lower ends of the foremost vertical member, a tow line slidably connected to said loop bridle, a line joining the upper and lower ends of the rearmost vertical member, and a drag element slidably connected to said line.

6. A streamer adapted for towing by aircraft comprising a substantially rectangular skeleton framework including vertical and longitudinal members, the vertical members being rigid and the framework being weighted at its two lower corners, a loop bridle joining the upper and lower ends of the foremost vertical member, a tow line slidably connected to said loop bridle, and a drag element connected to the rear of said framework.

CHARLES D. YOUNG. 

